Cerebral Autoregulation (CA) maintains a steady cerebral blood flow within a normal range regardless the variations of blood pressure and other bio-information. CA is a phenomenon describing automatic cerebral regulation to maintain a steady cerebral blood flow (CBF), or cerebral blood volume (CBV). Studies of CA modeling may involve with cerebral hemodynamics, intracranial hemodynamics, CSF dynamics, and ICP dynamics.In this paper, we employed the electric analog of intracranial dynamics to implement the CA simulator with Matlab platform. The model of the arterial-arteriolar cerebrovascular bed was proposed by Ursino with description of blood dynamics and biomechanics from the viewpoints of both cerebral circulation and intracranial space. With the fulfillment of this CA simulator, we can successfully the dynamics of blood vessels in brain subject to possible variations toward cerebral autoregulation.  We demonstrated the CA relations of wall thickness vs. radius of artery, hydraulic conductance vs. radius of artery, blood volume vs. radius of artery, elastic stress vs. radius of artery, smooth muscle tension vs. radius of artery, middle cerebral artery vs. transmural pressure, and temporal responses of artery radius and cerebral blood flow.